Coupling for a container valve

ABSTRACT

A coupling serving for connecting a double valve on a pressure container with a content of pressure gas, such as CO 2 , and a liquid, such as beer, to a pressure-gas source and a tap for drawing the liquid respectively. The valve comprises a blockable gas and liquid passage respectively, and the coupling comprises a housing for coaxial mounting on an upper flange on the valve, a slide which is placed in the housing and which can be displaced by means of a hand grip between an upper position where the valve is closed and a lower position where the valve is open; an elastomeric sleeve secured onto the slide and forming sealing between the slide and the valve flange in the mounted position of the coupling; a mainly tubular plunger secured in the slide; and a gas chamber formed between the plunger, the sleeve, and an inner wall in the slide. The plunger serves to open the valve in the lower position of the slide so that connection is made between the liquid passage of the valve and a liquid outlet on the slide via the chamber of the plunger, and connection is made between the gas passage of the valve and a gas outlet on the slide via the gas chamber. On the plunger is a seat for a sealing ring made in one piece with the sleeve which furthermore is arranged in such a way that the sealing ring is lifted free of the seat in the mounted condition of the coupling, and abuts against the seat in the dismantled condition of the coupling. This structure is simple and inexpensive and provides a better security against gas outflow when the coupling is dismantled than known so far.

BACKGROUND ART

The invention relates to a coupling for connecting a double valvedefining an axis and placed on a pressure container containing pressuregas, such as CO₂, and liquid, such as beer, to a pressure-gas source anda tap for drawing the liquid, respectively, whereby the valve comprisesa blockable gas and liquid passage, respectively, and the couplingcomprises a housing for coaxial mounting on an upper flange on thevalve; a slide which is placed in the housing and which can be displacedby means of a hand grip between an upper position where the valve isclosed and a lower position where the valve is open, an elastomericsleeve secured onto the slide and forming sealing between the slide andthe valve flange in the mounted position of the coupling, a tubularplunger secured in the slide; and a gas chamber formed between theplunger, the sleeve, and an inner wall in the slide; whereby the plungerserves to open the valve in the lower position of the slide so that aconnection is made between the liquid passage of the valve and a liquidoutlet on the slide via the chamber of the plunger, and a connection ismade between the gas passage of the valve and a gas outlet on the slidevia the gas chamber.

GB Patent No. 1 239 908 discloses such a coupling. In this case, a metalpipe is placed in the gas chamber of the coupling; the pipe is securedto the bottom of the elastomeric sleeve of the coupling by means of anoutwardly directed flange. The metal pipe extends upwards along theinner side of the sleeve and has an inwardly directed collar abuttingagainst an elastomeric ring in an annular groove in the plunger in thedismantled position of the coupling. During mounting, the sleeve iscompressed whereby the inwardly directed collar of the metal pipe islifted from its abutment on the elastomeric ring so that there is openedfor inlet of gas to the gas passage of the valve and thereby to thepressure container. The object of this structure is to eliminate thepossibility of gas flowing out of a dismantled coupling.

However, this structure is complicated and expensive as it is made up ofseveral components and in addition to this the sealing effect is unsafein the dismantled position of the coupling. The latter is especially dueto the fact that the elastomeric ring is inserted loosely in a groove inthe plunger, and leaks can be formed between the plunger and theprojecting elastomeric ring when the metal pipe affects this ring with amoment that—seen in cross-section—is likely to distort the elastomericring. The moment is caused by the quite considerable, in proportion tothe structure, axial forces that are generated due to the building up ofgas pressure in the gas chamber and the decompression of the sleeve, andthat are transmitted to the elastomeric ring via the metal pipe.

The structure furthermore means that the metal pipe must extend upwardlyin the gas chamber and the already narrow passage area is thereforefurther reduced. In order to allow the gas to pass, the metal pipe mustfurthermore be so fragile that it will contribute to making the sealingbetween the elastomeric ring and the inwardly directed collar of themetal pipe unsafe in a dismantled coupling.

The object of the invention is to show a coupling of the kind mentionedin the opening paragraph that, with a simple and inexpensive structure,provides a better guarantee against gas outflow when the coupling isdismantled than known so far.

SUMMARY OF THE INVENTION

The novel and unique features according to the invention, whereby thisis achieved, is the fact that a seat for a sealing ring is made in onepiece with the plunger, the sealing ring is made in one piece with thesleeve which is furthermore arranged in such a way that the sealing ringis lifted free of the seat in the mounted condition of the coupling, andabuts against the seat in the dismantled condition of the coupling. Thisstructure does not require any extra components and there are no looseparts. It is therefore inexpensive to manufacture and forms a safe andeffective sealing for the pressure gas when the coupling is dismantled.

In an especially simple embodiment, an outwardly directed collar can bemade on the lower pressure foot on the plunger for activating the valve;the top side of the collar forms a seat for the sealing ring.

Above the seat, the plunger can furthermore have a first, preferablycylindrical section and in continuation of this, a second, preferablycylindrical section with a smaller diameter than the first section. Indismantled condition of the coupling, the sealing ring can thenadvantageously enclose the first cylindrical section in contact with orat a short distance from this when the coupling is dismantled and thesealing ring abuts against the seat on the plunger. The result of thisis that the first cylindrical section in co-operation with the sealingring will contribute to seal against outflowing gas when the coupling isdismantled.

The sleeve can furthermore be arranged in such a way that it is deformedwhen the coupling is mounted and thereby its sealing ring is axiallydisplaced past the first cylindrical section on the plunger whereby thefree passage area for the gas is increased.

By forming the elastomeric sleeve with a cross section having a V-shapewith radially, outwardly directed point, the sleeve obtains anadvantageously flat compressibility characteristic allowing for aconsiderable, axial compression of the sleeve without at the same time agreat increase of the forces used to compress the sleeve.

An effective and safe sealing between the slide and the valve flange isobtained if the sleeve furthermore has a downwards converging sealinglip under the sealing ring.

The sealing ring which is made in one piece with the elastomeric sleevecan advantageously be stabilised and stiffened by an insertedreinforcing ring of e.g. stainless steel.

When the coupling is dismantled, liquid in the plunger chamber can runor drip out and pollute the surroundings. In order to avoid thisdisadvantage, the pressure foot can have an inwardly directed collarforming a seat for a non-return flap placed in the tubular plungertogether with a superjacent compression spring to keep the non-returnflap abutting against said seat. The non-return flap functions as anon-return valve during operation but is closed for reflux when thecoupling is dismantled.

Conventionally, the liquid outlet is lead axially out through thehousing, but in an advantageous embodiment according to the invention,the liquid outlet together with the gas inlet is lead sideways outthrough an axially extending mortise in the side wall of the housing.Thereby, an expedient piping to the gas source and the barrel tap withan attractive appearance is obtained. At the same time, the chamber inthe housing above the slide is left free for the hand grip.

The hand grip can furthermore be pivotally mounted about a swing axis inthe housing and be made to run with pressure pins across curved pressuresurfaces on each side of the slide when the hand grip is pressed downwhereby the pressure surfaces have such a form that the pins at firstdrive the plunger down to mounted position for finally locking the handgrip.

The pressure surfaces can furthermore be formed as the lower side ofcurved tracks placed on each side of the slide serving for guides forthe pressure pins. In order to be able to lead the pressure pins down toengage with these guide tracks, axial introduction tracks can be madethat extend from the guide tracks to the top side of the slide.

A conventional coupling has a centrally placed compression spring forholding the slide in its upper position. The coupling according to theinvention can instead have at least one extension spring acting betweenthe housing and the slide, the extension spring is displaced radiallyrelative to the axis of the housing so that the handle grip can swingacross this axis and thereby obtains an expedient placing of the angleover which the hand grip can swing.

The invention will be explained in greater detail below, describing onlyan example of an embodiment with reference to the drawing, in which

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an axial sectional view through a coupling according to theinvention mounted on a double valve on a pressure container,

FIG. 2 is an axial sectional view through the coupling in FIG. 1 indismantled condition,

FIG. 3 is on a larger scale an axial sectional view through anelastomeric sleeve for the coupling in FIG. 1 and 2,

FIG. 4 is a view of the coupling in FIG. 1 and 2 partly in axialsection, and

FIG. 5 is a sectional view taken along the line V—V of FIG. 4.

In FIG. 1 is seen a coupling 1 mounted on a double valve 2 tightlyfastened in a connection piece 3 on a pressure container 4 fordistribution of a liquid, such as beer or soft drinks, under pressure ofa gas, which typically can be CO₂. The container and the double valveare only shown in fragments.

At the top, the valve has a flange 5 and the coupling has gripping jaws6 for gripping under the flange 5 for detachably fastening the couplingon the valve. This operation takes place by pushing the couplingcrosswise across the flange of the valve.

DETAILED DESCRIPTION OF AN EMBODIMENT

The coupling comprises a housing 7 with a slide 8 that can be lead froman upper position (FIG. 2 and 4) to the lower position shown in FIG. 1by means of a hand grip 9.

A mainly tubular plunger 10 with a pressure foot 11 is placed in theslide 8 which for example can be made of plastic. At the top, theplunger is connected to a liquid outlet 12. The plunger 10 can forexample be made of metal.

A cup 13 is furthermore fastened in the slide. The cup has a relativelythin thickness of plate and is expediently made of stainless steel.

The edge of the cup is beaded around a collar 15 on an elastomericsleeve 16 serving for forming a sealing the slide 8 and the valve 2 inthe situation shown in FIG. 1 where the coupling 1 is fastened to theflange 5 of the valve 2 and the slide 8 is pressed down to its lowerposition by actuating the hand grip 9.

The valve is open in this lower position as the plunger 10 with itspressure foot 11 has pressed a valve ring 17 axially downwards so thatopenings 18 in a riser pipe 19 are uncovered. The liquid is then pressedby the pressure gas up through the riser pipe 19 and via the openings 18in the riser pipe further through the tubular plunger 10 to the liquidoutlet 12 which via a hose or a pipe (not shown) is connected to a tap(not shown) for drawing the liquid.

A gas chamber 20 is delimited by the plunger 10, the sleeve 16, and aninner wall 21 in the cup 13. A gas inlet 22, which via a hose or a pipe(not shown) is connected to a pressure-gas source, e.g. a gas cylinder(not shown), is lead into the gas chamber 20. The gas can now flow intothe container via the gas chamber 20 and a space between the sleeve 16and the plunger 10.

In the position shown in FIG. 1, the coupling is in its workingposition. When the coupling 1 is to be dismantled, the slide 8 is liftedwith the hand grip 9 after which the coupling can be dismantled. FIG. 2shows a dismantled coupling which is assumed to be in continuous openconnection with the pressure-gas source. However, the sleeve shuts offgas outflow to the surroundings where an accumulation of e.g. CO₂ can beharmful or fatal to persons living there.

The elastomeric sleeve 16 is seen best in FIG. 3 and as mentioned it hasa collar 15 around which the edge 14 of the cup 13 is beaded, the cup isonly seen in fragments in the figure. The sleeve has a first conicalsection 23 extending from the collar 15 and a second conical section 24extending from the first conical section 23. Seen in cross-section, thetwo sections 23 and 24 together form a V the point of which is facingradially outwards. At the transition between the two sections, anannular groove 25 is made inside so that the sleeve has a reduced wallthickness on this spot.

The second section 24 is carried on into a third section 26 with asomewhat larger conicity than the two other sections. Between the secondand the third section there is furthermore a sealing ring 27 integratedwith the sleeve with an inserted reinforcing ring 28 of e.g. metal.

Above the pressure foot 11, the plunger 10 has a first cylindricalsection 29 with a diameter corresponding to the diameter of the sleeveopening 30.

The axial length of the first cylindrical section 29 is proportioned sothat the sealing ring is lead into the area around the secondcylindrical section 31 when the sleeve is compressed at mounting, asshown in FIG. 1. Thereby, a space 32 is formed between the plunger 8 andthe sealing ring 27, and as mentioned earlier this space allows the gasto pass.

The sleeve is made of an elastomer, such as rubber, and it can becompressed to a highly reduced height without a drastic increase in thecompression forces in consequence of its V-shaped cross section whichcauses the sleeve to function as some kind of bellows with the qualitiesof a compression spring as its wall during compression is pressedradially outwards with a mutual folding between the two sections 23 and24 at the thinner wall area in the groove 25. At the same time, thethird section 26 functions as a sealing lip 26 ensuring effectivesealing between the slide 8 and the valve flange 5 when the coupling 1is mounted on the valve 2 and this valve is open.

In the dismantled position shown in FIG. 2, the sleeve 16 is howeverdecompressed so that the sealing ring 27 in consequence of the springeffect of the sleeve is made to abut tightly against the upper side 33of an outwardly directed collar 11′formed on the pressure foot 11 andtherefore acts as seat for the sealing ring. The coupling is now shutoff to gas outflow.

As shown in FIG. 4 and 5, the hand grip 9 is shaped as a fork with twoprongs 34 pivotally mounted with bearings 35 on the inside of thehousing 7, and an operating lever 36 extending out through a mortise 37in the housing.

As shown in FIG. 4, the prongs 34 of the fork form an angle with theoperating lever. At the end, each prong 34 has an inwardly directed pin38 extending into the tracks 39 of a curved guide; the tracks are madeon each side of the slide 8.

The lower side of each guide track forms a pressure surface 40 on theslide 8. When the hand grip 9 is swung from the position shown in FIG. 2and 4 to the one shown in FIG. 1, the pins run across this pressuresurface 40 so that the slide 8 is pressed down to its lower positionwhere the hand grip finally is locked due to the shape of the pressuresurfaces.

When the hand grip 9 is swung from the position shown in FIG. 1 to theone shown in FIG. 2 and 4, the pins 38 run along the upper side 41 ofthe guide tracks 39 so that the slide 8 is lifted.

Extension springs 42 acting between the slide 8 and the housing 1 andwhich are displaced relative to the coupling axis also serve for liftingthe slide and holding it in the upper position shown in FIG. 2 and 4.

By means of axially extending introduction tracks 43 extending from theguide tracks 39 to the top side of the slide 8, the pins can be pushedinto the guide tracks 39 when the hand grip is in its lower swingposition.

As shown, both the liquid outlet 12 and the gas inlet 22 are extendingsideways out through the housing via an axially extending mortise 44made in the side wall of the housing and allowing the liquid outlet andthe gas inlet to move axially relative to the housing when the slide islead back and forth between its two positions.

As described above, the sleeve ensures that gas do not flow out of adismantled coupling. The liquid that still is in the tubular plunger 10at dismantling and possibly in the connections to the tap will howeverstill be able to run or drip out of the dismantled coupling and pollutethe surroundings.

In order to prevent this disadvantage, a non-return valve in the form ofa non-return flap is placed in the plunger, the non-return flap is heldin abutment against an inwardly directed collar 11″ on the pressure foot11 by a compression spring 46 when the coupling is dismantled while itbreaks loose of this seat in the mounted and activated position of thecoupling and allows liquid to pass.

What is claimed is:
 1. A coupling for connecting a pressure container toa pressure-gas source the pressure container having a double valve witha flange and containing a pressure gas and a liquid, the couplingcomprising: a housing for coaxial mounting of an upper flange on thedouble valve; a slide within the housing that is displaceable between anupper position where the valve is closed and a lower position where thevalve is open; a tubular elastomeric sleeve having one end secured ontothe slide and an opposing sealing lip end that forms a seal against thevalve flange when the coupling is mounted on the container, saidelastomeric sleeve further including an inwardly directed sealing ringadjacent to the sealing lip end; a tubular plunger secured in the slide;and a gas chamber defined by the elastomeric sleeve, the plunger and aninner wall of the slide.
 2. A coupling according to claim 1 wherein thesealing ring is made in one piece with the elastomeric sleeve.
 3. Acoupling according to claim 1, wherein the plunger includes a seat, afirst cylindrical section above the seat and defining a first diameterand a second cylindrical section defining a diameter smaller than thefirst diameter, and wherein the sealing ring proximally encloses thefirst cylindrical section and abuts against a seat on the plunger.
 4. Acoupling according to claim 1, 2, or 3, wherein the elastomeric sleeveis deformed and its sealing ring is displaced axially past a firstcylindrical section on the plunger when the coupling is mounted.
 5. Acoupling according to claim 1, wherein the elastomeric sleeve includes adiverging first section and a converging second section extending fromthe first section and down to the sealing ring.
 6. A coupling accordingto claim 1, wherein the sealing ring comprises a rigid reinforcing ring.7. A coupling according to claim 1, wherein the plunger includes apressure foot with an inwardly directed collar forming a seat; thecoupling further including a superjacent compression spring that biasesa non-return flap within the plunger against said seat.
 8. A couplingaccording to claim 1, further including a liquid outlet and a gas inletextending through an axial slit in a side wall of the housing.
 9. Acoupling according to claim 1, wherein a hand grip for moving the slideis pivotally mounted about a swing axis in the housing and includes anoperating lever extending through a side wall of the housing, and apressure arm with two prongs with pressure pins that abut pressuresurfaces of the slide when the operating lever is moved downwards, saidpressure surfaces including a curved portion to facilitate movement ofthe slide and a flat portion to facilitate locking of the hand grip. 10.A coupling according to claim 1, further comprising at least oneextension spring acting between the housing and the slide and displacedradially about an axis of the housing.
 11. A coupling according to claim5, wherein, the elastomeric sleeve includes a converging third sectionthat forms the sealing lip.
 12. A coupling according to claim 9, furtherincluding tracks on each side of the slide, said tracks comprising:lower curved surfaces defining the pressure surfaces; and axialextensions for receiving the pressure pins and for bringing the pressurepins into engagement with the lower curved surfaces.
 13. A coupling formounting on a pressure container having a double value and a flange toconnect the container to a gas source and for dispensing the contents ofthe container, said coupling comprising: a housing and a hand gripmovably mounted thereon, a slide in the housing movable between open andclosed double valve positions by said hand grip to open and close thedouble valve, an elastomeric sleeve on said slide, one end of saidelastomeric sleeve defining a lip for sealing engagement with the flangea tubular plunger secured in the slide and defining a gas chamberbetween said sleeve and said plunger and said slide, said plungerdefining an external seat; said elastomeric sleeve connected at anopposite end to said movable slide, and said sleeve defining an internalsealing ring engageable with said external seat defined by said plunger,said sealing ring including a reinforcing ring of non-elastomericmaterial molded into said tubular elastomeric sleeve.
 14. The couplingaccording to claim 13 wherein said plunger includes a collar defining apressure foot, one side of said collar forming a valve seat, adapted forengagement with a valve ring provided on the double valve.
 15. Thecoupling according to claim 14 wherein said collar also defines a seatfor said sealing ring of said elastomeric sleeve.
 16. The couplingaccording to claim 15 wherein said elastomeric sleeve is deformable init's axial direction to accommodate axial motion of said tubularplunger.
 17. The coupling according to claim 16 wherein said elastomericsleeve has both diverging and converging sections between one end andsaid sealing ring to facilitate the axial deformation of the elastomericsleeve.
 18. The coupling according to claim 17 wherein said elastomericsleeve further defines a converging section at the opposite end thereofand said double valve including a flange engageable by said elastomericsleeve other end.
 19. A coupling for mounting on a pressure containerhaving a double valve and a flange to connect the container to a gassource and for dispensing the contents of the container, said couplingcomprising: a housing and a hand grip movably mounted thereon, a slidein the housing movable between open and closed double valve positions bysaid hand grip to open and close the double valve. an elastomeric sleeveon said slide, one end of said elastomeric sleeve defining a lip forsealing engagement with the flange a tubular plunger secured in theslide and defining a gas chamber between said sleeve and said plungerand said slide, said plunger defining an external seat, said elastomericsleeve connected at an opposite end to said movable slide, and saidsleeve defining an internal sealing ring engageable with said externalseat defined by said plunger, and said plunger defining an inwardlyformed collar, a spring acting against said collar to provide arestoring force on the double valve biasing the double valve toward itsclosed position.
 20. A coupling for mounting on a pressure containerhaving a double value and a flange to connect the container to a gassource and for dispensing the contents of the container, said couplingcomprising: a housing and a hand grip movably mounted thereon, a slidein the housing movable between open and closed double valve positions bysaid hand grip to open and close the double valve. an elastomeric sleeveon said slide, one end of said elastomeric sleeve defining a lip forsealing engagement with the flange a tubular plunger secured in theslide and defining a gas chamber between said sleeve and said plungerand said slide, said plunger defining an external seat, said elastomericsleeve connected at an opposite end to said movable slide, and saidsleeve defining an internal sealing ring engageable with said externalseat defined by said plunger, and a spring acting against said plungerto provide a restoring force on the double valve to urge the doublevalve toward a closed position.